Can we simply file a bifurcation and if so, how do we go about doing that?

My fiancé filed for divorce in 2007. He and his ex never finalized the divorce. In 2012, he received a 5 year notice of dismissal. He filed the required form to keep the case open. He and his ex are on great terms, no fighting, no problems and no issues with regard to the kids. They are both procrastinators and she's flaky. Getting her to follow through with finalizing will be next to impossible. She has trouble completing day to day tasks. This will probably not happen. We are now getting married next year and obviously we need this finalized.